Wisconsin wildlife have evolved a range of adaptations to help them survive the harsh winter conditions that we experience here in the Northwoods of Wisconsin. Conditions like extreme cold that we have been having this winter, deep snow (that we have yet to get this year), and limitations on food availability. Some animals grow a thicker coat of fur, like white tailed deer, coyotes, and foxes. White-Tailed Deer grow a thicker, denser coat during the colder months. They have an underlayer of insulating fur called guard hairs that help keep them warm. Some animals change their behavior. For example, black bears hibernate through the winter months to conserve energy. During summer and fall they eat large amounts of food to build up fat reserves, which sustains them during the months – long sleep. When bears hibernate, their body temperature drops, their heart rates slow, and they don’t need to eat, drink, or urinate.
Chipmunks and ground squirrels will do a similar thing. They will enter a state of torpor, which is a deep sleep that conserves energy. They can do this for weeks at a time and then wake up to eat food they have already stored away. Other animals that are masters at foraging and storing food are red squirrels and woodpeckers. Red squirrels are pretty active in the winter and rely on the food that they have stored up from the fall. They typically bury pine cones and other seeds underground or hide them in tree cavities. Woodpeckers store food in tree bark or other crevices to eat during the winter. Their specialized beaks allow them to peck through tree bark to get access to the insect larvae, even in frozen conditions.
Snowshoe hares adapt in a couple of ways. They can change their fur color from brown during the summer to white in the winter, which really allows them to blend in the snowy landscape and protect themselves from predators. They also have large wide feet that act like natural snowshoes, which is why they are named snowshoe hares. Their large and wide feet allow them to stay on top of the snow allowing them to escape from predators quickly.
One of the most fascinating animals to survive the Wisconsin winters are Chickadees. Chickadees have a core body temperature of 104 degrees F, even in frigid temperatures. They have a high metabolism that requires them to feed frequently, but also helps them maintain body heat. They are great at foraging and increasing their fat storage before the winter temperatures arrive. They also have a dense layer of feathers that they fluff up to trap more air in, which then acts as insulation to keep them warm, and they actually grown an extra layer of down feathers during the winter to help insulate. Chickadees also go into a state of torpor where they drop their body temperature and slow their metabolism at night.
For more information contact Kayla Littleton, Forest County Land Conservation and Land Information Director at 715-478-1387 or by e-mail at